Valved fittings are often utilized in aircraft fueling systems which are of the crashworthy type wherein valve structure closes in the event that the fitting is subjected to high impact forces. Such fittings permit valves to automatically close in the vent of an aircraft crash to prevent fuel leakage, and fires.
It is an object of the invention to provide a valved Tee assembly fitting which permits fluid lines to communicate with a tank or reservoir, and wherein automatic closing of a valve occurs in the event of high impact forces being imposed upon the valve structure.
Another object of the invention is to provide a valved Tee assembly fitting for connecting the interior of a tank with a fuel line wherein valve structure controls the communication of the fitting with the tank, and internal fluid pressure within the fitting aids in maintaining the valve closed, and a manual operation is required to shift the valve to an open position.
An additional object of the invention is to provide a valve assembly fitting for interconnecting a tank and a fluid line wherein the valve is locked in the open position by a manual actuator, release of the manual actuator permits the valve to be closed by a spring action, and the fluid pressure within the fitting assists in maintaining the valve closed.
In the practice of the invention a Tee fitting has a body which includes axially aligned fluid line ports, and a transversely disposed extension adapted to be inserted into a tank. A mounting surface encircles the extension, and openings or orifices are defined in the extension side wall to establish selective communication between the interior of the fitting and the tank.
An annular cup-shaped valve is axially displaceable within the extension moveable between an open position which clears the side wall openings, and a closed position wherein the wall of the valve closes the openings. The valve includes oppositely disposed fluid faces of differential area wherein when the valve is closed, the fluid pressure within the fitting assists in maintaining the valve in the closed position.
Movement of the valve from the closed to the open position is usually produced through a manual actuator which includes a plunger slidably supported upon the fitting body. The plunger includes a plurality of ball detents selectively cooperating with a fixed locking recess defined upon the body, and a manually displaceable rod positions the ball detents between operative and inoperative conditions. The ball detents are released from their locking position by a manual pull upon the rod, while pushing the rod initially shifts the valve from the closed to the open position, and such movement aids in placing the ball detents in their locked condition upon the valve being fully opened.
The valve body is provided with a frangible portion intermediate the fluid line port portion and the extension, and the mounting surface for the valve body is disposed adjacent the extension whereby impact forces imposed upon the valve body will cause the line portion to separate from the extension. The valve actuator merely abuts the valve whereby fracture, and displacement of the line portion, imposes no damaging forces upon the valve, and the valve is permitted to automatically close under the biasing force imposed thereon by a compression spring.
The components of the Tee valve assembly may be readily manufactured, and the automatic and manual operation of the valve is highly dependable.